The International Maritime Organisation (IMO), a UN body, has issued a revised handbook on the global maritime distress and safety system (GMDSS), according to Shipping Gazette. The updated version provides the principles on which the GMDSS is based, radio communication requirements and recommendations, operational performance standards and technical specifications to be met by GMDSS equipment and procedures. The GMDSS manual is for use by ship personnel, shore operators, trainers, administrations, regulators and those concerned with ship communication. In addition to tracing, the development and concepts of the GMDSS, its components of carriage requirements and operational procedures, the manual also includes excerpts from the relevant Safety of Life at Sea regulations, supporting resolutions and circulars, IMO performance standards and related information providing technical details of radio equipment among other communication matters, the Shipping Gazette adds.